Sending email using Smtp.mail.microsoftonline.com

Question

The context:

We’re a small company that does not have an Exchange Server (or anyone dedicated to it) yet we still need to have/send emails.

Answer 1

looking in Reflector on UseDefaultCredentials property, you can see that it also changes the trasnport.Credentials value, so when you called this property with a false value, it changed the transport credentials to null. the problem is that you called this property after setting the credentials in the line before that, it nullified the credentials.

so bottom line, you shouldn't set the credentials and call this property afterwise.